Background: Pure curcumin has been reported to down-regulate the expression of WT1 in leukemic cells. However, the molecular mechanism underlying the down-regulation of WT1 by curcumin is not completely delineated. The purpose of this present study is to identify a new miRNA-mediated mechanism which plays an important role in the anti-proliferation effects of curcumin in leukemic cells. Methods: K562 and HL-60 cells were treated with different concentrations of curcumin for 24 and 48 hours, the level of miR-15a/16-1 and WT1 were detected by qRT-PCR and Western blotting. WT1 expression and cell proliferation were detected by Western blotting and CCK-8, after curcumin treated-K562 and HL-60 cells were transfected with anti-miR-15a/16-1 oligonucleotides. Results: We found that pure curcumin upregulated the expression of miR-15a/16-1 and downregulated the expression of WT1 in leukemic cells and primary acute myeloid leukemia (AML) cells. Overexpression of miR-15a/16-1 deduced the protein level of WT1 in leukemic cells, but downregulation of WT1 by siRNA-WT1 could not increase the expression of miR-15a/16-1 in leukemic cells. These results reveal that curcumin induced-upregulation of miR-15a/16-1 is an early event upstream to downregulation of WT1. Furthermore, anti-miR-15a/16-1 oligonucleotides (AMO) partly reversed the downregulation of WT1 induced by pure curcumin in leukemic cells and AMO promoted the growth of curcumin treated-K562 and HL-60 cells. Conclusion: Thus, these data suggest for the first time that pure curcumin downregulated the expression of WT1 partly by upregulating the expression of miR-15a/16-1 in leukemic cells. miR-15a/16-1 mediated WT1 downregulation plays an important role in the anti-proliferation effect of curcumin in leukemic cells.
Mesenchymal stem cells (MSCs) and MSC-derived extracellular vesicles (MSC-EVs) are increasingly recognized for their therapeutic potential in regenerative medicine, driven by their capabilities in immunomodulation and tissue repair. However, MSCs present risks such as immunogenic responses, malignant transformation, and the potential to transmit infectious pathogens due to their intrinsic proliferative and differentiative abilities. In contrast, MSC-EVs, particularly exosomes (MSC-exosomes, 30–150 nm in diameter), offer a safer therapeutic profile. These acellular vesicles mitigate risks associated with immune rejection and tumorigenesis and are inherently incapable of forming ectopic tissues, thereby enhancing their clinical safety and applicability. This review highlights the therapeutic promise of MSC-exosomes especially focusing on the modulation of miRNA (one of bioactive molecules in MSC-EVs) profiles through various preconditioning strategies such as exposure to hypoxia, chemotherapeutic agents, inflammatory cytokines, and physical stimuli. Such conditioning is shown to optimize their therapeutic potential. Key miRNAs including miR-21, miR-146, miR-125a, miR-126, and miR-181a are particularly noted for their roles in facilitating tissue repair and modulating inflammatory responses. These functionalities position MSC-exosomes as a valuable tool in personalized medicine, particularly in the case of exosome-based interventions. Despite the potential of MSC-EVs, this review also acknowledged the limitations of traditional MSC therapies and advocates for a strategic pivot towards exosome-based modalities to enhance therapeutic outcomes. By discussing recent advances in detail and identifying remaining pitfalls, this review aims to guide future directions in improving the efficacy of MSC-exosome-based therapeutics. Additionally, miRNA variability in MSC-EVs presents challenges due to the diverse roles of miRNAs play in regulating gene expression and cell behavior. The miRNA content of MSC-EVs can be influenced by preconditioning strategies and differences in isolation and purification methods, which may alter the expression profiles of specific miRNAs, contributing to differences in their therapeutic effects.
18 April 2024 in Journal of Cardiothoracic Surgery
Background: The occurrence of massive retroperitoneal hematoma caused by intercostal artery bleeding is exceedingly uncommon. Case presentation: A middle-aged male presented to the hospital after a fall. Computed tomography scan revealed a massive retroperitoneal hematoma without any evidence of organ or major vessel rupture. The angiogram revealed extravasation from a branch of the twelfth intercostal artery, and successful transcatheter arterial embolization was performed on this specific artery. Conclusions: The possibility of intercostal artery rupture should be considered in cases of retroperitoneal hematomas, and accurate diagnosis can be achieved through imaging studies. Transcatheter arterial embolization represents an effective treatment modality.